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javaapache-kafkaspring-kafka

Spring Boot Kafka Batch Forwarding

I've configured my consumer to accept messages from a topic in batches. How do I forward it to a new topic?

I want each consumed messages to be forwarded as it's own message. So X amount of messages consumed will produce X amount of messages.

Here's my current setup:

@KafkaListener(topics = "input")
@SendTo("output")
public ConsumerRecords consume(ConsumerRecords records) {
  // Do things
  return records;
}

And here's the exception thrown:

org.springframework.kafka.KafkaException: No method found for class java.util.ArrayList

Solution

  • That functionality is not supported. In any case, you can't send a ConsumerRecord to a Producer.

    This works, though

    @KafkaListener(id = "foo", topics = "input")
@SendTo("output")
public List<String> consume(List<String> data) {
    return data;
}

    (where String is the type created by your deserializer).